Wow, it's hard to believe that on January 7, 2003, Apple's Safari browser first hit the scene. On that day at Macworld San Francisco, Steve Jobs announced that the company was releasing a beta version of its own web browser based on Apple's internal fork of the KHTML rendering engine, WebKit. Up until that time, Macs running OS X ran (believe it or not) Microsoft Internet Explorer for Mac as the default browser.
The first production version of Safari 1.0 was released on June 23, 2003 and was initially available as a separate download for Mac OS X 10.2 Jaguar and as the default browser for Mac OS X 10.3 Panther. At the time, Apple still made Internet Explorer available for download. Safari 2 shipped with Mac OS X 10.4 Tiger on April 29, 2005 as the only web browser included with the operating system.
In 2007, Safari became the built-in browser for iOS with the release of the first iPhone. Apple also released Safari 3 for Windows in 2007, and continued to develop and support Safari on the Windows platform until 2012.
We're now up to Safari 9.1, and I'd expect that like clockwork, Safari 10 will be announced this year at Apple's Worldwide Developer Conference. Like it or hate it, Safari has definitely made an impact on the lives of Apple users.
(Update: yes, 2016 - 2003 does equal 13, not 12)